The current X-ray imaging technology utilized in the medical industry is based on X-ray films. It requires a rather long patient exposure-time to X-ray and demands a long processing time to develop the X-ray films. Moreover, except for the location where the X-ray is taken, the X-ray films are not readily accessible to other medical professionals in case of an emergency far away from the primary care providers. These problems can be solved by utilizing semiconductor based X-ray detectors. The difference between using semiconductor detectors and conventional X-ray films is similar to the difference between utilizing a CCD camera and a normal film camera. In the latter, there is a need to develop the film and the exposure time is longer compared to CCD cameras. However, CCD cameras are not suitable for X-ray measurements due to the need to focus the X-ray beam which requires expensive and difficult optics. Progress in developing X-ray detectors has been rather slow. One of the major reasons for the lack of such development is the difficulty associated with the preparation and optimization of materials needed for the fabrication of these devices. The circuitry needed for control, communication and data management of these devices is readily available from other technologies such as charge coupled devices (CCD), spectroscopic analyzers, and imaging software and hardware. The materials required for X-ray detection and imaging devices are called wide bandgap semiconductors. Among this class of semiconductors are gallium nitride (GaN), indium nitride (InN), aluminum nitride (AlN), and silicon carbide (SiC). These semiconductors possess optoelectronic properties that make them nearly ideal radiation detectors with fast charge collection (fast response, low X-ray exposure), low leakage current (low noise) even at high temperatures, and they do not require a p-n junction for low noise operation of the detectors (low-cost, simple fabrication process). In addition, these materials are highly stable, chemically inert, and tolerant of harsh environments which makes them suitable for implantable devices. Moreover, these properties are ideal for uncooled detectors for X-ray spectroscopy which is finding increasing use in medical diagnostics. Due to the fast response of these devices, they can be accessed by computers for immediate analysis, storage, and motion video imaging.

This project focuses on the development of SiC radiation detectors. Our goal is to develop the technology needed for the fabrication of low-cost, miniature, highly sensitive radiation detectors for X-ray and higher energy radiation that can replace X-ray films and expensive CCD devices currently used in medical diagnostics.